American elm (Ulmus americana)
Model Reliability: Medium
| GCM SCENARIO | % Area Occ | Ave IV | Sum IV | Future/Current IV |
|---|---|---|---|---|
| Actual | 29.9 | 6.4 | 56000 | N/A |
| RFimp | 38.3 | 4 | 45247 | 0.81 |
| CCSM45 | 63 | 3.6 | 65966 | 1.46 |
| CCSM85 | 75.8 | 3.9 | 85968 | 1.9 |
| GFDL45 | 72.7 | 4 | 85005 | 1.88 |
| GFDL85 | 84.1 | 4.2 | 103249 | 2.28 |
| HAD45 | 78.4 | 3.9 | 89911 | 1.99 |
| HAD85 | 86.1 | 4.2 | 107259 | 2.37 |
| GCM45 | 80.6 | 3.4 | 80324 | 1.78 |
| GCM85 | 88.3 | 3.8 | 98856 | 2.18 |
Regional Summary Tree Tables
Summaries for tree species are available for a variety of geographies, in both PDF and Excel format. These summaries are based on Version 4 of the Climate Change Tree Atlas
Interpretation Guide
American elm is widely distributed (33.3% of area, third behind red maple and black cherry), dense, and with high IV. Though hit hard by Dutch elm disease, it still abundant in the western portion of the study area. Its medium reliable model suggests a large increase in suitable habitat by 2100, primarily into the south and east portions of the eastern US. Additionally, because the species is sporatically present across those regions, the SHIFT model does suggest a potential for a fair amount of natural colonization. However, the fact that the species is susceptible to Dutch elm disease (DED) may swamp any potential expansion of the species, and we would expect overall declines in the species by 2100 even though some tolerant cultivars are now becoming available. Despite the DED, it is rated as moderately adaptable with an overall capability rating, because of its current abundance and increase in modelled habitat, is very good. However, this rating could change due to DED. SHIFT also suggests it as a good infill species (though only use resistant varieties).
Family: Ulmaceae
Guild: pioneer, spring-dispersed, moist-site tolerant
Functional Lifeform: large deciduous tree
| 4 | -0.80 |
| 0.30 |  |
MODFACs
What traits will impact American elm's ability to adapt to climate change, and in what way?:
Primary Positive Traits
Environment habitat specificity
Primary Negative Traits
Disease Insect pests